Issues with heater for 07 Chevy Impala, idle we have no heat, drive we have heat?

[Andrew H]

I have an 07 Impala with heater issues. The heater works great after the car warms up while driving , which seams to take a little longer than i would think. Anyway, the issue is i could be driving for an hour with the heater going just find and then if i park the car and it idles, the heater will start to blow colder air after a few minutes. The heater will take off than after i start to drive again. Also, if i just start the car and let it sit for 20 minutes, no heat. Drive one minute and then its hot. I'm lost and need help. Thanks.

[stemcell]

You either have low coolant or there is an air bubble in your cooling system.
You should be under warranty. See your dealer.

[steve h]

Sounds like low coolant level.

[waleedakhter]

it shld still be under warranty take it to the dealer